Undeclared variable 'g' not faulted at edit time and can lead to run-time errors.

[chrisjj]

Expected Behavior

Edit-time error: 'The variable 'g' does not exist.'

Current Behavior

No edit-time error. Sometimes run-time error: 'NulPointerException' (sic).

Steps to Reproduce

In an empty sketch, enter

g=null;

on in a real sketch, accidentally include that statement out of scope of a declaration of g in the sketch.

Your Environment

• Processing version:
  3.3.6
• Operating System and OS version:
  Windows 7.

Possible Causes / Solutions

Processing's internal 'g' varaible leaking into the sketch's scope.

[MLanghof]

That's because there is a PGraphics object named g in the same class your code gets placed in - it's the thing you effectively draw on. And if you set that one to null, bad things will happen indeed.

[benfry]

Closing since there's not a great solution for this; the g object is there and as implemented, we can't prevent people from messing with it.

[chrisjj]

How about make the syntax checker fault use of a dangerous name?

Else add to the docs a warning and list of the dangerous names?

[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.